@bradthrasher
Have you used the support documentation searchbox? http://en.support.wordpress.com Simply type in the term and you will be able to tell what it means by the search results you get back by simply observing the context.

@frannienic
That's a support documentation page containg the instructions for installing an author's grid widget. That support entry does not answer bradthrasher's idea submission for Staff to consider creating a Glossary.

The front page of the support forum here provides links for specific forums in the sidebar. This thread is entered into the Ideas Forum which is for submitting Ideas and suggestions for WP.com Staff to consider. http://en.forums.wordpress.com/forum/ideas